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Related papers: The Cusp/Core problem and the Secondary Infall Mod…

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In the present paper, we improve the "Extended Secondary Infall Model" (ESIM) of Williams et al. (2004) to obtain further insights on the cusp/core problem. The model takes into account the effect of ordered and random angular momentum,…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-04 A. Del Popolo , P. Kroupa

We test the Secondary Infall Model (SIM) by direct comparison with the results of N-body simulations. Eight cluster-size and six galactic-size dark matter haloes have been selected at $z=0$ and re-simulated with high resolution. Based on…

Astrophysics · Physics 2008-11-26 Y. Ascasibar , Y. Hoffman , S. Gottloeber

Context. The cusp-core discrepancy is one of the major problems in astrophysics. It results from comparing the observed mass distribution of galaxies with the predictions of Cold Dark Matter simulations. The latter predict a cuspy density…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 J. van Eymeren , C. Trachternach , B. S. Koribalski , R. -J. Dettmar

N-body simulations and analytical calculations of the gravitational collapse in an expanding universe predict that halos should form with a diverging inner density profile, the cusp. There are some observational indications that the dark…

Astrophysics · Physics 2009-11-06 Amr El-Zant , Isaac Shlosman , Yehuda Hoffman

We derive inner dark matter halo density profiles for a sample of 165 low-mass galaxies using rotation curves obtained from high-quality, long-slit optical spectra assuming minimal disks and spherical symmetry. For $\rho(r) \sim…

Astrophysics · Physics 2009-11-10 Kristine Spekkens , Riccardo Giovanelli , Martha P. Haynes

We study the role of systematic effects in observational studies of the cusp-core problem under the minimum disc approximation using a suite of high-resolution (25-pc softening length) hydrodynamical simulations of dwarf galaxies. We mimic…

Astrophysics of Galaxies · Physics 2016-12-19 Juan C. B. Pineda , Christopher C. Hayward , Volker Springel , Claudia Mendes de Oliveira

Standard cosmology has many successes on large scales, but faces some fundamental difficulties on small, galactic scales. One such difficulty is the cusp/core problem. High resolution observations of the rotation curves for dark matter…

Astrophysics · Physics 2010-11-30 Da-Ming Chen , Stacy McGaugh

Rotation curves of galaxies probe their total mass distributions, including dark matter. Dwarf galaxies are excellent systems to investigate the dark matter density distribution, as they tend to have larger fractions of dark matter compared…

Bose-Einstein-condensed dark matter, also called scalar-field dark matter (SFDM), has become a popular alternative to cold dark matter (CDM), because it predicts galactic cores, in contrast to the cusps of CDM halos ("cusp-core problem").…

Astrophysics of Galaxies · Physics 2022-06-08 Kevin Pils , Tanja Rindler-Daller

The observed rotation curves of low surface brightness (LSB) galaxies play an essential role in studying dark matter, and indicate that there exists a central constant density dark matter core. However, the cosmological N-body simulations…

Astrophysics of Galaxies · Physics 2021-07-02 Xiaobo Gong , Meirong Tang , Zhaoyi Xu

Cusp-core problem is a controversial problem on galactic dark matter haloes. Cosmological N-body simulations has demonstrated that galactic dark matter haloes have a cuspy density profile at the centre. However, baryonic physics may affect…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Shigeki Inoue , Takayuki R. Saitoh

We use the secondary infall model described in Del Popolo (2009), which takes into account the effect of dynamical friction, ordered and random angular momentum, baryons adiabatic contraction and dark matter baryons interplay, to study how…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 A. Del Popolo

We compare proposed solutions to the core vs cusp issue of spiral galaxies, which has also been framed as a diversity problem, and demonstrate that the cuspiness of dark matter halos is correlated with the stellar surface brightness. We…

Astrophysics of Galaxies · Physics 2020-06-17 Manoj Kaplinghat , Tao Ren , Hai-Bo Yu

In this work, we extend the model proposed by White concerning the post-collapse evolution of density peaks while considering the role of angular momentum. On a timescale smaller than the peak collapse, $t_{0}$, the inner regions of the…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-12 Antonino Del Popolo , Saeed Fakhry

The existence of two kinematically and chemically distinct stellar subpopulations in the Sculptor and Fornax dwarf galaxies offers the opportunity to constrain the density profile of their matter haloes by measuring the mass contained…

The distribution of dark matter in the inner regions of galaxies poses a key challenge for small-scale {\Lambda}CDM cosmology. While cold dark matter simulations predict cuspy inner density profiles, observations of low surface brightness…

Astrophysics of Galaxies · Physics 2026-02-09 Sougata Sarkar , Prerana Biswas , Veselina Kalinova , Nirupam Roy , Narendra Nath Patra , Sushma Kurapati

A generalized version of the Spherical Infall Model (SIM) is used to study the effect of angular momentum on the final density profile of a spherical structure. The numerical method presented is able to handle a variety of initial density…

Astrophysics · Physics 2009-11-07 Nicos Hiotelis

The condensation of baryons within a dark matter (DM) halo during galaxy formation should result in some contraction of the halo as the combined system settles into equilibrium. We quantify this effect on the cuspy primordial halos…

Astrophysics of Galaxies · Physics 2022-09-21 Pengfei Li , Stacy S. McGaugh , Federico Lelli , James M. Schombert , Marcel S. Pawlowski

We present a suite of 16 high-resolution hydrodynamic simulations of an isolated dwarf galaxy (gaseous and stellar disk plus a stellar bulge) within an initially cuspy dark matter (DM) halo, including self-interactions between the DM…

Astrophysics of Galaxies · Physics 2022-04-20 Jan D. Burger , Jesús Zavala , Laura V. Sales , Mark Vogelsberger , Federico Marinacci , Paul Torrey

The cold dark matter model of structure formation faces apparent problems on galactic scales. Several threads point to excessive halo concentration, including central densities that rise too steeply with decreasing radius. Yet, random…

Astrophysics of Galaxies · Physics 2016-07-27 Amr El-Zant , Jonathan Freundlich , Francoise Combes
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